This invention relates generally to improvements in heating apparatus, and more particularly to heating apparatus utilizing a heat transfer member, such as a heat pipe, for heating a liquid in a chamber or storage container.
Heretofore, heating apparatus utilized to heat the interior of a chamber or tank of a heater assembly, such as in a hot water heater or in a hemodialysis device, and the like, included a combined heat producing and heat transfer element. In some instances the heating apparatus was built into the heater assembly such that a failure of the heating apparatus or any of its associated components required that the entire heater assembly be discarded. For example, in some presently available, domestic electric hot water heaters, the heating element is secured permanently within the tank. This type of hot water heater is relatively reliable for long periods of time. However, should a malfunction occur, it may require that the entire hot water heater be discarded and replaced or a major overhaul of the heater may be required. Furthermore, heating elements are generally of a fixed heat capacity type. If additional heat is required, a different, larger capacity heating element is required. This frequently requires that the entire heater assembly, including the tank, be replaced.
Additionally, in presently available hot water heaters, such as those wherein the heating element is mounted in the wall of the tank, if the heating element needs to be replaced, it is necessary to drain the water from the tank to permit removal of the heating element therein. Still another problem with electrical hot water heaters, and the like, is that of a possibility of an electrical short circuit. This may be hazardous to persons using or repairing the hot water heater.
As will be described in detail hereinafter, the present invention provides an improvement over previously proposed heating apparatus by separating the heat-producing function from the heat-transfer function in a heating apparatus utilized for heating a medium in a chamber or storage container, e.g. a water tank. Preferably, the heat-transfer function is achieved with a heat pipe.
Heretofore it has been proposed to utilize a heat pipe in a fossil fuel fired hot water heater as disclosed in U.S. Pat. No. 3,854,454. As will be apparent from the following description, the present invention differs from the heat pipe water heater disclosed in this patent. In particular, and as more fully described hereinafter, the heating apparatus of the present invention has a novel modular design and construction and is primarily designed and constructed for use in an electric heating device, such as in an electric hot water heater or in a hemodialysis device.